Doosan D50S-5 Operation & Maintenance Manual page 196

Inspect the top and bottom hooks on forks used Inspect the top and bottom hooks on forks used
on hook type carriages and tubes on shaft on hook type carriages and tubes on shaft
mounted forks. mounted forks.
Forks with cracks should be removed from Forks with cracks should be removed from
service. service.
"Wet Test" magnetic particle inspection is "Wet Test" magnetic particle inspection is
generally preferred due to its sensitivity and the generally preferred due to its sensitivity and the
ease ease of of
equipment is usually recommended so it can be equipment is usually recommended so it can be
moved to the lift truck. moved to the lift truck.
Inspectors should be trained and qualified in Inspectors should be trained and qualified in
accordance with The American Society for Non accordance with The American Society for Non
Destructive Testing, Level II Qualifications. Destructive Testing, Level II Qualifications.
2. 2. Check the angle between the upper face of the
Check the angle between the upper face of the
blade and the front face of the shank. The fork blade and the front face of the shank. The fork
should be withdrawn from service if angle (C) should be withdrawn from service if angle (C)
exceeds 93 degrees or deviates by more than 3 exceeds 93 degrees or deviates by more than 3
degrees from an original angle other than 90 degrees from an original angle other than 90
degrees, as may be found in some special degrees, as may be found in some special
application forks. application forks.
Maintenance Section Maintenance Section
5. 5. Check the fork blade (J) and shank (H) for wear Check the fork blade (J) and shank (H) for wear
with special attention to the heel (G). The fork with special attention to the heel (G). The fork
should be withdrawn from service if the should be withdrawn from service if the
thickness is reduced to 90 percent or less of the thickness is reduced to 90 percent or less of the
original thickness. original thickness.
Fork blade length may also be reduced by wear, Fork blade length may also be reduced by wear,
especially especially
Remove the forks from service when the blade Remove the forks from service when the blade
length is no longer adequate for the intended length is no longer adequate for the intended
loads. loads.
interpreting interpreting the the results. results.
on on tapered tapered forks forks and and
Portable Portable
4. 4. Check the difference in height of one fork tip to Check the difference in height of one fork tip to
the other when mounted on the fork carrier. A the other when mounted on the fork carrier. A
difference in fork tip height can result in uneven difference in fork tip height can result in uneven
support of the load and cause problems with support of the load and cause problems with
entering loads. entering loads.
The maximum recommended difference in fork The maximum recommended difference in fork
tip elevation (F) is 6.5 mm (0.25") for pallet forks tip elevation (F) is 6.5 mm (0.25") for pallet forks
and 3 mm (0.125") for fully tapered forks. The and 3 mm (0.125") for fully tapered forks. The
maximum maximum
elevation between the two or more forks is 3 elevation between the two or more forks is 3
percent of blade length (L). percent of blade length (L).
Replace one or both forks when the difference in Replace one or both forks when the difference in
fork tip height exceeds the maximum allowable fork tip height exceeds the maximum allowable
difference. Contact your local DOOSAN Lift difference. Contact your local DOOSAN Lift
Truck Dealer for further information. Truck Dealer for further information.
195 195
Shaft mounted forks may use set collars or Shaft mounted forks may use set collars or
spacers on the shaft to either side of the fork. spacers on the shaft to either side of the fork.
They may also use U bolts, pins, or similar They may also use U bolts, pins, or similar
devices which engage the fork through the top devices which engage the fork through the top
structure of the carriage. structure of the carriage.
8. 8. Check fork markings (N) for legibility. Renew Check fork markings (N) for legibility. Renew
platens. platens.
markings as required to retain legibility. markings as required to retain legibility.
9. 9. a. a. Lift the mast and operate the tilt control Lift the mast and operate the tilt control
lever, until the top surface of the forks is lever, until the top surface of the forks is
allowable allowable difference difference in in fork fork tip tip